Do's and Don'ts of Cable Routing (Part 2)

Here’s the second in my two-part blog post on best practices for cable runs. You can read Part 1, which has some important background information about this project, here.

DO RUN ETHERNET EVERYWHERE

Having access to open walls during construction is a rare opportunity, so I ran Ethernet cable everywhere I could think of, including into my garage. I ran four cables into rooms in which I knew I’d be connecting more than one piece of gear (e.g., into my home theater and my home office). If you’re going through the hassle of stringing cable, you might as well and go all the way and take it to as many places as you can access. Even if you have just a single Ethernet port, you can always plug in a router to gain more later.

DON’T RUN CAT5 CABLES PARALLEL TO POWER CABLES

My installer knows better than this, but I asked him to do it anyway because I ignored the advice above and decided to run Ethernet to my kitchen island after we had already installed the cable chases and poured the foundation. Running data cable parallel to power cable typically results in interference, but we decided to take a chance since this run is only about 15 feet long. If I do encounter problems, I can simply disconnect this cable from the network and the problem will be solved.

DO CROSS POWER CABLES AT A 90-DEGREE ANGLE

It’s impossible to avoid putting your Cat5 cable in close proximity to power cables, but there’s an easy way of avoiding interference problems: Hang your Ethernet cables from your trusses to kept them away from power cables, and when they must drop down to enter the wall’s top plate, have it cross any power cables at a 90-degree angle.

DON’T BUNDLE YOUR CABLE TIGHTLY

It’s okay to run your data, telephone, and coax video cable together, but you should avoid tying the cables into overly tight bundles. You should also make sure your cable turns are gentle; a kinked cable can have a significant and negative impact on network throughput.

DO USE MUD RINGS

Use mud rings instead of junction boxes for Ethernet, coax, and speaker cable runs (you can find them for both retrofit and new-construction applications). Since you’re dealing with low voltage, it’s not necessary to terminate the cable inside the confines of a box. Mud rings are much easier to work with: You won’t need to stuff excess cable into the box, which means you’re much less likely to kink the cable and throttle your throughput.

Comments

somewhat related to the above, I have a video door phone (intercom) system that runs CAT5e cabling in between the different stations (doorbell, master monitor, slave monitor) and the CAT5e cable is used to transmit power from the MASTER monitor to the other stations. I had passed CAT5e cabling for data networks and telephone through a 25mm PVC typesconduit and had also passed the above CAT5e cable for the intercom system in the same conduit (this is before I knew that the power was transmitted over this cable).

Since the video door phone is transmitting 18V (eighteen) to power up the other stations, do you think it is safe to leave them as-is (i.e. in the same conduit) or will I suffer degradation of service in my data networks and/or telephone.

I havent yet tested this as I am still working on the house - but any help is appreciated.

Can someone please explain to me what exactly is a "Home-Run"? I'm not sure I understand what it is for and how to actually do it. Please be as detailed as possible in your description.

Also, I have decided to run ethernet cabling all througout my house and am planning the entire project by myself. I am not a certified "Network Engineer" (YET) but I have a lot of knowledge on how to go about doing this. My house is already built, so this is probably going to be the most difficult part; trying to figure out how to actually run the cables through the walls. I plan to have an ethernet wall jack in every room of my house (there are a total of 5 rooms). I WOULD GREATLY APPRECIATE ANY ADVICE YOU CAN GIVE ME ON CABLING!

Also keep cables away from florescent lights and heat sourcses (such as incandescent lights). Florescent lights emit a lot of EM which can corrupt data and excessive heat is just not good for the cables (slower speeds, corrupted data).

When hanging cables make sure the bundle is supported every 4 to 6 feet. Too much sag causes the cable to stretch and deform which can damage the charateristics of it (slower speeds, corrupted data)

Make sure cables will stay dry and not get wet.(slower speeds, corrupted data).

One thing that is easily overlooked: put your wall jacks near wall power outlet. You're going to need a power source for for that PC, TV, and wireless phone/answering machine aren't you?
Seperate the power outlet and communications outlet with a stud between 'em.

I was a professional telecomunications cabler for 15 years. Any problems or questions let me know.

Just a heads up using the STP, it's kind of a pain in the but to terminate. But if you have to run parallel to the power, then it's the best way to go. (Some inspectors may not like it though) and there is usually a ground in the cable too (at least on when I've worked with it). If you're going to work with cat6, make sure you have room in your boxes/mudrings. It's not as forgiving as cat5e. And where you can get away with some sharp angles (greater than 80 degrees) with cat5, cat6 will fail a TDR test. cable ends have to be straight at both ends of the terminations (jack and Patch Panel). Use Velcro when possible for dressing in cat6. (all points if the cable run).

Those hyper links are great. I've yet to figure out how to work the strings into my media network, but I think the island would work fine. I've never tried to hang cable with those trusses. I think it would be all right as long as they are inside the walls.

I talked to my networking contractor about using Cat6, but he recommended Cat5e. It's a little cheaper, and that cable will still enable me to set up a gigabit Ethernet network.

If I thought anyone would ever run fiber to my curb, I would have given more consideration to using Cat6. As it stands, my new home is in a rural area outside the city limits. I don't think anyone will be running fiber there any time soon.

I've seen where running UTP next to power has caused major problems and it took forever to find. I think I would have requested STP to ensure no interference. It's harder to terminate, but you can run it next to almost anything.

CAT-5 cable can be run parallel to power lines though, a good couple of feet away is always nice. The interference should be canceled-out from the twisted pairs. Or, at least that's what cisco taught me :p.